Self-stopping and self-repeating mechanism for cramophones, talking machines, and the like



June 8 1926. k 1,588,389

' F. B. MITCHELL SELF STOPPING AND SELF REPEATING MECHANISM FOR GRAMOPHONES,

. TALKING MACHINES, AND THE LIKE Filed May 15, 1925 A h A mvsuton FignQ- F 40, F291],

Patented June 8, 1926.

;SEIsF= ST-0ZPB-I NG AND- SELF-REBEATINGFMECHANISM .103 ioRAMomroNEs, "TALKING I .MAGHINES,MAND': EEHE LIKE. 7'

ap ication'- filed zray is, 1925,?Seria1' No.

on -ornearthereproducer or sound box I place-a-member carryingone or more tracers fine or -t-hinenough to enter the vrecord groove (hereinafter called the tracer) which may bemajdehf-metal too soft to wear the record orprov'ided with a; sapphirepoint 'or the like, and the tracer-is-so shaped or "mounted that it shalltransmit as-l-ittle sound -=as;'possible.

, I" also have a special arrangementiof cam action for operating the repetition sat'z'the outer edge. v

The tracer is so: mounted 1 that -When-the stylus is finishing-its Work on the record the tracer'pointshall be in thei'la'st circle of the :record ,3 groove. 7

The tracer is mountedjon arocking hearing so that :its point shall havei-movement towards the finish of the radial path ofthe -stylus over the record.

The movemest of thetracer 'Onitshearing 'Whenit can slip onthe smooth partbfthe record releases operating mechanism forfthe purpose otbrake or-repetition.

The 'tra'cer' point may be a -little in' radvance of its line of pivotation -:inwards towards the record axis:so thatitsvertic'al pressure on the record, when in action, will ive a s rin ressure'inwards and Will cause it to turninwardson its bearing as soon as it can slip. s

I If the tra'cer is Working in "afgrooveWh-ich is in advance of" the igr'oo've in which the stylus is" working, "then-the lateral movement of the reproducer imtheordinary -manner will help to force=thetracer out 'ofthe-last groove by its contact with ap'artyon to' tlle smooth part, should-the 'groove not havel'a natural run out from the'end; I

This tracer pushing 1 part "may also :torm a leg so that-in the event ofthe' reproduce'r falling on-the record or"turntahle"when it i "has no 'stylusneedle-initfthe shockwill be 30,628, and in Great.BritainMay 14,v I924.

received by the lleg and tthe parts will not be broken, din ypractl-ce it is found-'tthatiithe tracer-maybe madeiof tempered steelWire certain-"shape shown in "the accompanying drawlngs' to preventsound transmission. M

The inventionn'rlso comprisessundryapp a1*atusttor repetition purposes {that shown in the accompanying drawings hemginthe 1 "form ot' a double "resetting "cam operate'd by 'contact Withltherecord. 4

To avoid complication I have only shown "one'form of the invention "but 'many forms havebeemmade *byune during experiments and of "course ithef invention Lis" capable of 1maI1yLmOdl fiCfitlGDS. i I-'v v1ll now proceed'to des'crihethe inventlon indetail, the novel features of .WhichI WIll finall point out-inthe appended claims,

reference being "had to the accompanying 'iFig. is a perspective jfront elevation of a reproducer-or. soun'dbox fitted for brake showsiaistop:arrangemeiit to prevent the reproducer:passrng oif 'the record, With the stylus S 1n action Inthe record groove.

by the bra-ke IB, which is in -action gon the record l i i i r Fig, 3 a left-(face or end View Ofi-tllfl stylus part ofthe reproducer with the stylus S in action and ,just reaching-the end ofthe record groove R Italso shows the-tracer lbalooutto leavef the record orbe pushed out, and lithe --clot t-edgpa'rt :shows a the tracer :A pushed; out or after itjhas slipped on the smooth partof the record. 7 1 'Fig. 4 is a; perspective View 'ofatrac'er-A and its-rocking pivotationA 'From :this cambe seen" the means by --Wh-ich-When it rocksthe-arm A allo-Wsthe brake friction x acti-on only, on the surface of the record,

mounted on .an ordinary tone-armwhich -Fig2 isthexsame, withfthe stylus lifted pad B to falLi'nto action=toalloW-the drag of --themovingrecord to lift the reproducer and :StylHS Out of action' as shown in :Fig-

ure'i2.

l igzo shows the 'same:apparatus-With the ad'dition' of the douhle=resetting cam C 0 7 Fig. 6 showsaar'cam and-lorakeor friction member vvithi the cam: slightly: turned so that thei'stop rides :on' the"movin*g" record preventiingrcontact' of the' moving roam "with athe fre'cord 'until tlie m'ember' can *pass over the outer edge of the record as shown in Figure start.

F ig.7 in this the cam has turned further until the cam has made contact by presenting a longer radius; now the moving record will get a grip of same'and complete the re setting by turning the cam round and lifting the friction member. I

Fig. 8 shows how it resets the brake member .B and lowers the stylus by presenting a receding face to the record as it turns.

Fig. 9 is a plan of a rocking member showing a hole A and groove A to receive the end of the tracer A "the clamp A is shown turned out of action.

Fig. 10 is a tracer Wire.

Fig. 11 shows the two Figures 9 and 10' clamped together.

Figure 1 shows an ordinary gramophone turntable with a record disc R to turn in the direction of the arrow. The tracer A is in action thereon. The tone arm is mounted to rotate in the fixed bearing M. The reproducer may be turned upon axis T out of action, with the stylus pointing upwards, when not in use. Brake action only is shown. i

The action is as follows ;A needle S is inserted and the machine setin motion, the

tracer A enters a record groove inwards of that of the stylus, as the machine works the whole'is gradually approaching the centre of the record, the tracer will reach the last circle of the record groove before the stylus. and will either jump out towards the record centre of itself or will wait to be pushed out by the continued inward travel of thestylus and reproducer.

WVhen the tracer and its'holder A moves with the extension A the movement of the latter allows the lever'B to fall and the part B touching the moving record, the latter pulls the lever to the vertical position. As lever B is too long,-this raises the reproducer. out of action as shown in Figure 2 and the rub of the friction pad. B on the record causes the brake pad B to be moved outwards by the frictional tangential drag on the record and after two or three revolutions of the record the machine will stop. -The pull of the moving record. on the pad will move the arm outwards towards Xand to prevent the reproducer passing over the edge of the record a stop L is provided with which the member T is adapted to engage.

The stop is adjustable for different size records as shown by the steps L and L A spring may be provided to cause the arm to go outwards'as soon as the stylus and reproducer are lifted as stated.

I will now morefully desc. ibe the action with reference to Figures 3, 4L, 9, l0 and 11. The tracer pin is in this form, a thin needle with the. working point bent at nearly a to cover same and the screw is tightened' as shown in Figure 11. V. 1

This tracer is mounted on the reproducer T so that 1ts point PIOJECtS lower than the point of the stylus when the latter is lifted and will touch the record before the stylus when placing the reproducer inpositionthus it always works under spring. pressure on the record.

, it will be noticed that the tracer point is not directly under the line of its pivotation when at work, see Figures 11 and 3, so that the spring pressure on its point will, while turning the block on its pivot, cause the 7 point of the tracer to move to the left, in

other words the spring pressure of the tracer on the record gives the point a spring tendency to jump sideways. It cannot however travel sideways and the block cannot turn while the point is unable to slip as shown in Figure 3 in a record groove,"but as soon as the point gets on a smooth part of the record as in Figure 2 and by dotted, lines in Figure 3 upward pressure on the V tracer point (its spring pressure) causes it to jump inwards as shown moving the block A and the extension A which latter permits the brake or operating member B to fall and either stop the machine or repeat.

Referring to Figures 5, 6, 7 and 8 thereproducer lifting parts are here shown as previously described but with the addition of repetition parts which act as follows Cam wheel C is mounted on an axis 0 and may be surrounded by a rubber band as it is to rotate by friction on the record.

When the parts mentioned come into action at the finish of the record and the brake member B falls the pin B can pass in and move with member B from the position shown inFigure5 to the position shown in Figure 6.

The cam wheel is heavy onthe right hand so that if free it will turn. In the position Figure 5 this wheel cannot turn as thestop block C on the cam C cannot pass the pin B in B, but directly the member B falls, pin B no longer prevents rotation of cam C Figure 6. In this position the tone arm T is being moved out and thereproducer is lifted by the friction member B. As the armC rides on the record surface the cam C cannot turn enough, to touch the record until it reaches the. edge and the arm C passes over the edge of the record (the cam remaining over the record). Now the cam C can turn andarm C? falls still more as shown in Figure 7the cam now making contact with the record. ord now grips same and causes it to turn completely. Directlythe record begins to turn the .cam wheel the reproducer'is still The turning rec-- 7 masses further and the rotation' dr' the cam bound) passage of the pin B and lever B to the leift otherwise there is uanger ef its rebounding inwards at each operationfiantl not coming-to rest, This stop is long enough for the tracer aneniberA to -re'tu n to' th'e position shown an Figure} by gravity where it holds up the member I To bequite-sure that the reproducer when it is thrown outwards for restart stops exactly at-thecorrect-position I provide a stop member having stop positions adjustable for brake purposes, for ten inch records or for twelve inch for example shown at L Figure 1. This stop member may have an adjust able screw in each face for fine adjustment at L and L or the arm bearing may be arranged to slide laterally.

There is a part at T Figures 3 and 5 fit-which serves two purposes: One is that if a reproducer is allowed to fall on a record when there is no stylus needle in, the shock will be received by the part and no harm done to the working parts. The other purpose is that if there is any dilficulty (owing to an extra deep groove) for the tracer point to go out of the last groove the continued movement of the approaching reproducer will force it out by means of the extension T.

1. Mechanical automatic control mechanism for talking machines and the like, comprising a tone arm control device for coacting with the record, and a tracer to actuate the device and tracking in the record groove in advance of the talking machine stylus.

2. Automatic mechanism for talking machines, comp-rising a tone arm control device for oacting with the record, a tracer tracking in the record groove in advance of the talking machine stylus, and means operated by the tracer for applying the control device to the record at the end of the reproduction upon the escape of the said tracer from the inner end of the record groove.

3. Automatic mechanism for talking machines and the like, comprising a tone arm control device for coacting with the record, a resilient tracer carried with the talking machine reproducer and tracking in the record groove and movable therefrom at the end of the reproduction, and a release device operated by the movement of the tracer for permitting the control device to be operated.

4. Automatic mechanism for talking machines and the like, including a tone arm control device for coacting with the-record,

means ter reventing the operation m le controhdevice duringreproductioma cer tracking in the record groove in faavance of the tit-Bein machine stylus, and operated by the tracer dor releasing saidcom 'trol. device preventing means a'tthe and at thereproduction-and upontlie' at the -sai'd tra'cer 'fromthe--iI1ne'i""ei1tl erzthe'reeord groove. V A

Automatic repeating mechanism aer talking machines and the "like romp brake pad, means norm-allypreventing are operation of the brake'p adduring reproduction, a tracer engaging the record groove I to release said brake pad restraining means at the en'd of a reproduction so that the brake pad contacts"with-the accord remove the reproducer to the outer part of the record and means for automatically re-setting the brake pad and its restraining means.-

6. Automatic repeating mechanism for talking machines and the like comprising a brake pad, means normally preventing the operation of the brake pad during reproduction, a tracer engaging the record groove to release said brake pad restraining means at the end of a reproduction so that the brake pad contacts with the record to move the reproducer to the outer part of the record, and a weighted cam adapted to co-operate with the record for re-setting the brake pad and its restraining means.

7. Automatic repeating mechanism for talking machines and the like comprising a brake pad, means normally preventing the operation of the brake pad during reproduction, a tracer engaging the record groove to release said brake pad restraining means at the end of a reproduction so that the brake pad contacts with the record to move the reproducer to the outer part of the record, a weighted cam adapted to co-operate with the record for re-setting the brake pad and its restraining means, and means for preventing said weighted cam from contacting with the record until the reproducer reaches the outer edge of said record.

8. Automatic repeating mechanism for talking machines and the like comprising a brake pad, means normally preventing the operation of the brake pad during reproduction, a tracer engaging the record. groove to release said brake pad restraining means at the end of a reproduction so that v the brake contacts with the record to move the reproducer to the outer part of the reco-rd, a weighted cam adapted to co-operate with the record for re-setting the brake pad and its restraining means, and an arm movable with said cam and adapted to ride upon the record surface so as to prevent the cam contacting with the record until the reproducer has reached the: outer edge thereof.

9. Automatic repeating mechanism for talking machines and the like comprising a operation of the brake pad during reproduction, a tracer engaging the record groove to releaseebrake pad restraining means at the end of a reproduction so that the brake contacts with the record to move the reproduce-r 'to-the outer part of the record, a weighted cam adapted to co-operate with the record for re-setting the brake pad and its restraining means and a stop device for preventing the reproducer. moving beyond the outer edge of said record.

. 10. In a talking machine or the like, a,

tracer tracking in the record groove, a tone arm- 'control device for coacting with the record and actuated by thetracer upon its escape from said groove. 7

11. In a talking machine and the like, a resilient tracer tracking in the record groove, a reproducer supporting the tracer and acting to force the tracer out of the record groove at the end of the reproduction, and

a control device for the reproducer actuated by said tracer at theend of a reproduction. 12. In a talking machine and the like, the combination of a reproducer including a stylus and a tracer tracking in the record groove in advance of the stylus, and areproducer control device coacting With the record and actuated by the said tracer at the end of the reproduction. Dated this lst day of May 1925.

FRANK BOWLEY MITCHELL. 

